So, here's a review after using this case for a year:
It does its job of protecting the gear, but the only problem which I got with it is that the X contour fader on the Denon Prime 4+ is not in a proper position inside the case and can be easily damaged, which happened to me, unfortunately - it punched though the case, making a hole, and the x contour fader itself got bent and damaged. There is a small notch for that part of the controller, but the device is easily moving inside the case, which can cause damage to it, as it is not anyhow fixed - some straps could be great for additional protection and fixing the device in place inside the case.
On the good side - the case fits power cables, mains lead plug (5 slots) and RCA cable. If you purchase separately a decksaver (I highly recommend to do so) for Prime 4/4+, then that will also nicely fit inside the case and will give additional protection